Professional learning is a social enterprise where peers rely on the expertise and support of one another to adopt innovative practices. Reciprocal interactions in a community of practice, where teachers take responsibility for each other's learning and development, may provide an effective means of supporting situated professional learning. We propose a collaborative apprenticeship model featuring reciprocal interactions as an approach to promote professional development, encouraging peer-teachers to serve as modelers and coaches of strategies and ideas aimed at improving instruction. collaborative apprenticeship is designed to help teachers learn and implement new teaching skills and strategies through four development phases, beginning with implementation of best practices from a mentor to the development of their own. Teachers, in turn, contribute new ideas to their teaching environment and become future mentors in order to sustain skills and strategies across a community of teachers. In addition to the model, we discuss various influences related to affect, beliefs, environment, culture, cognition, and personality that characterize the nature of reciprocal interactions in order to stimulate collaborative apprenticeship. (c) 2005 Elsevier Ltd. All rights reserved.